For semiconductor chip manufacturing, a quality of materials is a key point to maintain constant and high quality of products. Titanium halide compounds, such as TiCl4 and TiI4, have been used as materials for deposition of Ti and TiN films in chip manufacturing industries. See, e.g., US2013/0115383 to Xinliang Lu et al.
TiI4 is very sensitive to the air and its quality needs to be controlled well for its usage in order to keep constant and high performance during manufacturing processes in semiconductors. U.S. Pat. No. 5,700,519 to Lam discloses a method for depositing ultra high purity titanium films by generating gaseous TiI4 in situ by reacting titanium metal starting material with gaseous iodide in a reaction chamber and purifying the TiI4 by a double distillation process to produce ultra high purity of greater than 99.998% TiI4.
A need remains for methods of purifying and storing TiI4 so that it is of suitable purity for vapor deposition of Titanium-containing films.